1. Field of the Invention
The present invention relates to a mechanism for processing items continuously fed on a base strip or tubing material, such as labels or sleeves to be applied to containers, in order to perform an operation on each item, in which each item provided with a bar code must be accurately positioned, this mechanism having a feed device to unreel the base material and a controlled processing device to perform the operation on the items.
The invention relates in particular, although not exclusively, to a mechanism for cutting items fed continuously and printed continuously on a strip or tubing, such as labels or sleeves to be placed on containers, in particular bottles, each of the printed surfaces having a printed indicium of the bar code type to enable the items to be severed one by one from the unreeled strip.
2. Description of the Related Art
A method of providing bottles or containers of this type with stretch or shrink labels is already known, i.e. which are elastically pulled over the item on which they elastically shrink or which are placed on the item without being deformed and then put through a heat shrinking process.
These sleeves are unreeled from tubing, i.e. from a continuous, flat reeled tube on which the various indicia or the sleeve label and a bar code are imprinted.
At the instant at which these sleeves are placed on the bottles, the tubing is unreeled and the machine tears off the sleeves one by one to engage them on the bottles.
However, this known solution has a certain number of disadvantages, the most important one being that a tear off line has to be made, separating two sleeves or two pieces of the tubing. This requires an operation in addition to that of printing the tube. This operation is delicate since it requires accurate alignment with the sleeve printing system.
Document U.S. Pat. No. 5,383,130 discloses an in-line printing system for folded sheets. This system uses marks of a predetermined design. The system detects this mark in order to make the fold. A device of this type requires an expensive process of applying specific marks on the sheets to be folded.
Another method, known from document U.S. Pat. No. 5,095,219, involves cutting a strip of material to ensure that products are cut to the correct length. Each bar of the bar codes is transferred into a signal which is in turn converted in order to obtain cutting accuracy. It is the length measurement in each bar code which is used to operate the machine. A method of this type is complex and requires expensive operating means.
Similar processes are known for items such as labels, unreeled from a continuous strip.